Your picture is way too blurry to tell anything. Did you match it to any known Doubled dies? I did a quick search and 1974D has a few DDOs but they all seem to be very minor.
As far as I can tell it matches a Doubled Die obverse Lincoln....if im not wording it right I apologize, I'm learning.
What did you match it to? Here is a good site to use: http://coppercoins.com/advsearch.php Again like I said, your picture is way to blurry to see anything. Also, with the doubling on the 74Ds that I looked at, you would need much closer and much clearer pictures.
If you are talking about the stuff along Lincoln's profile, that is consider MD (Mechanical doubling). Check this link out: http://www.error-ref.com/machine-doubling/ This is not true doubling. Here is a picture that hopefully will help explain the different types of doubling: Also, Youtube is about the worst place you could go for coin info. If you are interested in learning about true errors and varieties let us know and we can provide plenty of links.
Lol it's just you and me in this thread so far but no worries. Here are a few links that are really good to check out. Perhaps others will chime in and add theirs: http://coppercoins.com/advsearch.php http://www.lincolncentresource.com/ https://www.pcgs.com/PHOTOGRADE/ http://varietyvista.com/index.htm http://www.error-ref.com/ http://doubleddie.com/
